In our Using a CAPTCHA to prevent Spam article, we covered how a CAPTCHA can help you prevent Spam. In this article we'll go through step-by-step how to install the WP-reCAPTCHA plugins for WordPress. This plugin can provide CAPTCHA protection for both comments and registration on your blog.

1. Begin by logging into your WordPress Dashboard
2. From the Plugins area of your dashboard, search for and install WP-reCAPTCHA
3. Once you activated the plugin, you'll see a warning that reads: "You enabled reCAPTCHA, but some of the reCAPTCHA API Keys seem to be missing. Fix this" Click the Fix this link in the above warning to open the reCAPTCHA Options page (Settings > WP-reCAPTCHA)
   
   
4. To obtain your reCAPTCHA API Keys, open the "here" link in a new tab (Ctrl + left mouse click) from the following line under the Authentication heading:"These keys are required before you are able to do anything else. You can get the keys here."
5. This will open the Create a reCAPTCHA key page. Click the "Create Key" button.
   
   
6. On the next page you will see your Public and Private Keys. Copy each one into the appropriate field back in WP-reCAPTCHA options in your WordPress Dashboard. Make sure you copy each key to the appropriate field.
   
   
7. Scroll down and click the Save reCAPTCHA Changes button.

By default, reCAPTCHA is enabled for comments and registration on your blog. You can adjust these settings as you like for your site.